An installation of the type in question is described and illustrated in document FR 2 872 148.
During the treatment of the container, a microwave field is emitted inside the enclosure and this field develops into the pumping chamber through the sleeve. The microwaves that propagate inside the sleeve and inside the pumping chamber cause particles of the barrier material (carbon, silica or other compound) to form deposits therein, which contaminate the internal walls of the sleeve and the pumping chamber, or even the internal walls of the pumping circuit. Deposits form in the same way on the external wall of the injector that is dipped into the container.
For this reason, it is necessary for the sleeve and the injector, and also the pumping chamber, to be cleaned frequently. To do this, the sleeve and the injector have to be individually dismantled. Document FR 2 872 148 shows an arrangement that allows the sleeve to be fitted onto the enclosure and to be removed therefrom.
These operations are lengthy, have to be repeated as many times as the installation has treatment stations, and require the installation to be immobilized, which is expensive.
Moreover, the operators of these installations require ever higher production rates. An increase in manufacturing rate may admittedly be achieved by improvements made in certain places in the design of the various parts or constituent components of the installation. However, to obtain a satisfactory result, the time to execute the process of depositing the layer of barrier material cannot be shortened sufficiently in order to result in a significant increase in the production rate of the installation, which seems, in the current state of the art, to be able to be obtained only by significantly increasing the number of treatment stations of the installation. It follows that the problem associated with the constraints caused by having to clean the sleeves, the injectors and the pumping chamber, then becomes even more acute.